An advocacy group for minority police officers is calling for the resignation of Boston Police Commissioner Edward F. Davis, arguing that his administration disciplines officers of color more harshly than their white colleagues and operates an unfair system of promotions.

Larry Ellison, a Boston detective and president of the Massachusetts Association of Minority Law Enforcement Officers,
said during a meeting Tuesday night at the group’s Dorchester headquarters that the organization had taken a vote of no confidence in Davis and his second in command, Superintendent in Chief Daniel P. Linskey.

Ellison said in a brief interview after the meeting that he is calling for Davis to resign.

Among the issues Ellison raised was the demotion of Jerome Hall-Brewster, a black officer who was stripped of his detective’s badge last week after the department found that he did not follow up on a September 2012 case involving Edwin Alemany, who is now charged with the kidnapping and murder of Amy Lord, a 24-year-old South Boston woman, on July 23.

A spokeswoman for Davis declined to comment Tuesday. The commissioner has previously expressed a commitment to diversity in the department.

Dot Joyce, a spokeswoman for Mayor Thomas M. Menino, said the mayor has “full confidence in the commissioner’s ability to run the department in the most professional manner possible.”

In condemning the commissioner, Ellison said the Police Department’s brief investigation of Hall-Brewster’s actions violated his due process rights.

The Massachusetts Association of Minority Law Enforcement Officers says Davis disciplines officers of color more harshly than their white colleagues.

Hall-Brewster did not attend the meeting, but his brother, Boston Detective Arthur Hall-Brewster, said he is being scapegoated.

“Davis is a liar,” Arthur Hall-Brewster said, growing emotional.

Arthur Hall-Brewster said he bears no ill will toward the residents of South Boston. He said they were “set up” to cheer when Davis announced his brother’s demotion at a recent public safety meeting.

Officials have said Jerome Hall-Brewster did not pursue Alemany in a 2012 attack on a woman in Boston because he did not think he had probable cause for an arrest. They have also said he did not respond to phone calls and e-mails about the case from the crime lab.

His lawyer contends that he did not respond to three e-mail messages from a lab staff member, but responded within 24 hours to a fourth message, in which the specialist asked whether Hall-Brewster believed the items he submitted for DNA testing belonged to the suspect in the 2012 attack.

Jimmy Myers, a veteran Boston broadcaster, urged the meeting attendees to engage the news media in their fight.

“You’re going to have to do a little legwork,” Myers said.

Also at Tuesday’s meeting, Ellison mentioned recent department promotions that he said upset minority officers.

According to the organization of minority law enforcement officers, Davis promoted four white male officers and a white female officer on Friday, while nine officers of color had the same test scores but were not considered.

Later that afternoon, Davis promoted two black male officers after the organization contacted him, the group said.

“Everything with us is a fight,” said Ellison, adding that the administration has made a “conscious effort” to limit the number of minority officers promoted.

During Friday’s round of promotions, the department bypassed two white officers who received the same score as the officers who were promoted, said Mark Parolin, vice president of the Boston Police Superior Officers Federation.

He said that the department is short-staffed on supervisors and that the union wanted all of the officers who qualified for sergeant to be promoted.

Five of the six campaigns could not be reached for comment late Tuesday night, but one of the candidates, Councilor Robert Consalvo, referred to Davis’s handling of the investigation into the terrorist attack when he gave him a ringing endorsement in June.

“Obviously, he was incredible during the terrorist bombings and showed true leadership,” Consalvo told the Globe.

Mayoral candidate Martin J. Walsh, a state representative, had kind words for the officers association on Tuesday night.

“I appreciate MAMLEO and the officers they represent,” Walsh said in a statement. “Although we’ve made progress, we all know we have a long way to go and a lot of work to do to make sure that our police force more accurately reflects the diversity of our city.”

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